Study Protocol: Multicenter Randomized Clinical Trial to Assess the Effect of Active versus Passive Recharge Burst Spinal Cord Stimulation on Pain Relief in Persistent Spinal Pain Syndrome Type II (“the Burst-Recharge Active Versus Passive (Burst-RAP) Protocol”)

Background: Spinal cord stimulation (SCS) has shown to be an effective treatment for patients with persistent spinal pain syndrome Type 2 (PSPS Type II). Important in SCS is the method used to deliver electrical charge. One such method is burst stimulation. Within burst stimulation, a recharge pattern is used to prevent buildup of charge in stimulated tissue. Two variations of burst waveforms are currently in use: one that employs active recharge and one that uses passive recharge. It has been suggested that differences exist between active and passive recharge paradigms related to both efficacy of pain relief and their underlying mechanism of action. Active recharge has been shown to activate both the medial spinal pathway, engaging cortical sensorimotor areas involved in location and intensity of pain, and lateral pathway, reaching brain areas involved with cognitive-emotional aspects of pain. Passive recharge has been suggested to act via modulation of thalamic neurons, which fire in a similar electrical pattern, and thereby modulate activity in various cortical areas including those related to motivational and emotional aspects of pain. The objective of this Randomized Clinical Trial (RCT) is to assess and compare the effect of active versus passive recharge Burst SCS on pain relief in PSPS Type II patients. Methods: : This multicenter RCT will take place in 6 Dutch hospitals. PSPS Type II patients ( n=96 ) will be randomized into a group receiving either active or passive recharge burst. Following a successful trial period, patients are permanently implanted. Patients complete the pain catastrophizing score (PCS), numeric pain rating scale (NRS), patient vigilance and awareness questionnaire (PVAQ), hospital anxiety and depression scale (HADS), quality of life (EQ-5D), Oswestery disability index (ODI), patient global impression of change (PGIC) and painDETECT questionnaires at baseline, after trial, 1, 3, 6 and 12 months following implantation. Discussion: The BURST-RAP trial protocol will shed light on possible clinical differences and effectivity of pain relief (including emotional-motivational aspects between active and passive burst SCS in PSPS Type II patients. Trial registration: This trial is registered in the Netherlands Trial Register under registration number NL9194.